§ 1201-c. Credits against taxes administered by cities of one million or more. Any utility company which is subject to the supervision of the public service commission and is required to grant rebates or discounts on bills for energy services in accordance with article two-I of the general city law shall be entitled to a credit for such rebates or discounts against the amount of tax to be paid pursuant to any gross receipts tax imposed by a local law adopted pursuant to subdivision (a) of section twelve hundred one of this article. The amounts of such rebates or discounts shall not be treated as affecting or reducing the gross receipts otherwise subject to tax under such gross receipts tax or reducing the amount of tax imposed by or pursuant to any authorization contained in this chapter.